RE: [drakelist] shelf life of tubes
Goss, Ed [EMAIL PROTECTED] made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED]; drakelist@www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes Gary Poland [EMAIL PROTECTED] made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] shelf life of tubes
Im using WW2 vintage JAN tubes in some of my audio equipment and it works great. But, it just depends. Mark W0NCl-Original Message-From: Goss, Ed [EMAIL PROTECTED]To: Gary Poland [EMAIL PROTECTED]; [EMAIL PROTECTED]; drakelist@www.zerobeat.netSent: Fri, 5 May 2006 09:09:34 -0400Subject: RE: [drakelist] shelf life of tubes "Goss, Ed" [EMAIL PROTECTED] made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED]; drakelist@www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes "Gary Poland" [EMAIL PROTECTED] made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] shelf life of tubes
Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Seems like I have seen something about storing transmitting tubes upright to prevent the filament (or other elements) from sagging. Also a recommendation to run with filament power only for several (?) hours after long term storage before applying HV. There WILL be some leakage past the glass-metal pin seals over time, and when the tube is powered up the getter will absorb some gas. I don't think this is much of a problem with small receiving tubes. There are still plenty of two-digit tubes from the 1930's that are running just fine, along with millions of tubes from the 40's - 60's. 73, Garey - K4OAH Atlanta Drake B C-Line Service CDs http://www.k4oah.com [EMAIL PROTECTED] wrote: Im using WW2 vintage JAN tubes in some of my audio equipment and it works great. But, it just depends. Mark W0NCl -Original Message- From: Goss, Ed [EMAIL PROTECTED] To: Gary Poland [EMAIL PROTECTED]; [EMAIL PROTECTED]; drakelist@www.zerobeat.net Sent: Fri, 5 May 2006 09:09:34 -0400 Subject: RE: [drakelist] shelf life of tubes Goss, Ed [EMAIL PROTECTED] mailto:Ed.Goss%40jhuapl.edu made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net [mailto:[EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net%5dOn Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED] mailto:abqcooks%40aol.com; drakelist@www.zerobeat.net mailto:drakelist%40www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes Gary Poland [EMAIL PROTECTED] mailto:gpoland1%40cinci.rr.com made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] shelf life of tubes
Dennis Monticelli [EMAIL PROTECTED] made an utterance to the drakelist gang -- I think it is a good idea to power up the filaments for a few hours before putting full voltage on a transmitting tube. I had the experience of putting some 20 year old NOS 6146Bs into a TS-820 (800V HV unloaded). For the first two days of approx 2 hrs use each, I had three occurances of brief single-shot HV shorts due to internal tube arcing. The arc only lasted milliseconds but was enough to dim the panel lights. Residual gas builds up over the years. A HV transmitting tube is highly dependent upon a good vacuum. Just a few hours of hot filament is enough to get the residual gas agitated and then captured by a hot getter flashing. After those several 6146 arc events, the tubes settled down and worked just fine. If I had given them some light exercise prior to installation, I'll bet those arcs never would have happened. On 5/5/06, Garey Barrell [EMAIL PROTECTED] wrote: Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Seems like I have seen something about storing transmitting tubes upright to prevent the filament (or other elements) from sagging. Also a recommendation to run with filament power only for several (?) hours after long term storage before applying HV. There WILL be some leakage past the glass-metal pin seals over time, and when the tube is powered up the getter will absorb some gas. I don't think this is much of a problem with small receiving tubes. There are still plenty of two-digit tubes from the 1930's that are running just fine, along with millions of tubes from the 40's - 60's. 73, Garey - K4OAH Atlanta Drake B C-Line Service CDs http://www.k4oah.com [EMAIL PROTECTED] wrote: Im using WW2 vintage JAN tubes in some of my audio equipment and it works great. But, it just depends. Mark W0NCl -Original Message- From: Goss, Ed [EMAIL PROTECTED] To: Gary Poland [EMAIL PROTECTED]; [EMAIL PROTECTED]; drakelist@www.zerobeat.net Sent: Fri, 5 May 2006 09:09:34 -0400 Subject: RE: [drakelist] shelf life of tubes Goss, Ed [EMAIL PROTECTED] mailto:Ed.Goss%40jhuapl.edu made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net [mailto:[EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net%5dOn Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED] mailto:abqcooks%40aol.com; drakelist@www.zerobeat.net mailto:drakelist%40www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes Gary Poland [EMAIL PROTECTED] mailto:gpoland1%40cinci.rr.com made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net --
Re: [drakelist] shelf life of tubes
kbgluxford [EMAIL PROTECTED] made an utterance to the drakelist gang -- I hesitated and Googled to no avail before offering my two cent's worth, but I seem to remember reading recommendations about bringing up the heaters or filaments very, very slowly (i.e. over hours rather than seconds) using a variac, soaking the tubes for several hours at rated voltage or just a tad below before applying voltages to the anode and screen (with suitable bias voltage to the control grid of course). I think that the article I read had a circuit of equipment designed to do all this, and provide metering of electrode currents, but I am blowed if I can find it now. The point made was that the getter in the tube can still be effective in removing gas, unless, of course, the vacuum seal was defective. RF Parts on their website has a paragraph or two on bringing up NOS tubes. 73 Kevin VK3DAP / ZL2DAP Dennis Monticelli wrote: Dennis Monticelli [EMAIL PROTECTED] made an utterance to the drakelist gang -- I think it is a good idea to power up the filaments for a few hours before putting full voltage on a transmitting tube. I had the experience of putting some 20 year old NOS 6146Bs into a TS-820 (800V HV unloaded). For the first two days of approx 2 hrs use each, I had three occurances of brief single-shot HV shorts due to internal tube arcing. The arc only lasted milliseconds but was enough to dim the panel lights. Residual gas builds up over the years. A HV transmitting tube is highly dependent upon a good vacuum. Just a few hours of hot filament is enough to get the residual gas agitated and then captured by a hot getter flashing. After those several 6146 arc events, the tubes settled down and worked just fine. If I had given them some light exercise prior to installation, I'll bet those arcs never would have happened. On 5/5/06, Garey Barrell [EMAIL PROTECTED] wrote: Garey Barrell [EMAIL PROTECTED] made an utterance to the drakelist gang -- Seems like I have seen something about storing transmitting tubes upright to prevent the filament (or other elements) from sagging. Also a recommendation to run with filament power only for several (?) hours after long term storage before applying HV. There WILL be some leakage past the glass-metal pin seals over time, and when the tube is powered up the getter will absorb some gas. I don't think this is much of a problem with small receiving tubes. There are still plenty of two-digit tubes from the 1930's that are running just fine, along with millions of tubes from the 40's - 60's. 73, Garey - K4OAH Atlanta Drake B C-Line Service CDs http://www.k4oah.com [EMAIL PROTECTED] wrote: Im using WW2 vintage JAN tubes in some of my audio equipment and it works great. But, it just depends. Mark W0NCl -Original Message- From: Goss, Ed [EMAIL PROTECTED] To: Gary Poland [EMAIL PROTECTED]; [EMAIL PROTECTED]; drakelist@www.zerobeat.net Sent: Fri, 5 May 2006 09:09:34 -0400 Subject: RE: [drakelist] shelf life of tubes Goss, Ed [EMAIL PROTECTED] mailto:Ed.Goss%40jhuapl.edu made an utterance to the drakelist gang -- There is no magic number; too many variables including design of the tube, how well the procedure for manufacturing was developed, how well the procedure was followed, quality control of fabrication equipment, handling of the tube after manufacture, and many others --Ed, N3CW-- -Original Message- From: [EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net [mailto:[EMAIL PROTECTED] mailto:owner-drakelist%40www.zerobeat.net%5dOn Behalf Of Gary Poland Sent: Thursday, May 04, 2006 7:44 PM To: [EMAIL PROTECTED] mailto:abqcooks%40aol.com; drakelist@www.zerobeat.net mailto:drakelist%40www.zerobeat.net Subject: Re: [drakelist] shelf life of tubes Gary Poland [EMAIL PROTECTED] mailto:gpoland1%40cinci.rr.com made an utterance to the drakelist gang -- Jim, A fellow at Eimac once told me that 3-500Z's will get gassy if left stored for long periods of time. Other then that I dont know. 73, Gary -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost:[EMAIL PROTECTED] - help in body of message Zerobeat Web Page: www.zerobeat.net - sponsored by www.tlchost.net -- -- Submissions:drakelist@www.zerobeat.net Unsubscribe:[EMAIL PROTECTED] - unsubscribe
